Spintronics or spin electronics represent a new generation of electronic, solid-state devices that utilize an intrinsic spin and magnetic moment of an electron, as well as the electron's charge. It is anticipated that spintronic devices will be smaller, more versatile, and have superior properties compared to their semiconductor counterparts. These properties may include reduced power consumption due to their inherent nonvolatility, more rapid switching speed, and a larger number of carriers.
Giant magnetoresistance (GMR) structures represent one known spintronic device that consists of magnetic films separated by a nonmagnetic layer. An applied magnetic field produces huge changes in the electric resistance of the magnetic films essentially turning on or turning off electron flow through the device. In this regard, GMR devices operate by switching the magnetization direction in the magnetic films by means of an external magnetic field in close proximity to the device. By switching the magnetic field, the electrical resistance of the device can be changed dramatically. This effect is exploited in some recording devices, such as, in computer hard disks. There are other devices that utilize this characteristic.
For example, a magnetic version of a random access memory (RAM) device may utilize a similar effect. Unlike many current RAM devices, a magnetic random access memory device would be nonvolatile, no information is lost when the power is switched off. One structure of this device includes two magnetic films separated by an insulating metal-oxide film. The electrons may tunnel through the metal-oxide layer when the magnetization of each of the magnetic films is properly oriented. Still another device may include magnetic films that sandwich a semiconductor material layer, like a silicon layer. This construction may form a hybrid device that may behave like a conventional transistor to be used in computing.
The pursuit of spintronics, however, has been hampered by poor properties and manufacturing methods. For example, in semiconductor spintronics, there have been intensive efforts to develop room-temperature magnetic semiconductors and carbon-based materials as spin-transporting channels, with only limited success. In particular, there is a focus on organic-based magnets, because organic-based magnets allow chemical tuning of the electronic and magnetic properties of the magnetic films. However, to incorporate these materials, quality thin films of the material must be made and, as yet, are generally unavailable.
In this regard, there remains a need for organic-based magnetic films with improved performance and methods for making such films, which are both cost effective and scalable.